One of my new M3Ti has a dent on the cone of its woofer driver right out of box so Axiom sent me a new woofer driver for replacement. This new woofer looks sort of weird so I'd like to make sure it is the exact one for the M3Ti before I start to work.

Here below are two items to confirm
1) The woofer is not of magnetic shielded and has 2 exposed ferro-magnets, one is sandwiched between metal structures, the other one is a donut lying on the very back of the unit.
2) The impedance of the woofer is 6 ohms as printed on the donut magnet, despite M3Ti's nominal impedance of 8 ohms.

Besides, do I need to use some sealant or other binding agent in the area where the woofer frame meets the front baffle of the cabinet during installation?